A single event upset (SEU) occurs in a electronic circuit device, such as a digital circuit, when the device is exposed to energetic ions and protons. This is a particular concern for circuit devices that are to be deployed for operation in space, such as Earth orbit.
Certain hardware components in integrated circuit processor devices (i.e., “chip sets”) are unusually sensitive to SEUs. Errors that occur in some components can cause a system to freeze, crash, generate exceptions, etc.